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Examples

The relationship between the Celsius and Fahrenheit scales for temperature is given by the formula \(F=\frac{9}{5}C+32,\) where \(F\) is the temperature in degrees Fahrenheit and \(C\) is the temperature in degrees Celsius. If the boiling point of curium is \(3110^{\circ}\)C, what is it in degrees Fahrenheit?

(A)
This wrong choice is \(3110\) divided by \(5\), which is just one step in the calculation. In order to get the right answer, you have to multiply this by \(9\) and add to the result \(32.\)

(B)Tip: Just because a number appears in the question doesn’t mean it is the answer.
This wrong choice is the boiling point of curium in degrees Celsius, as stated in the prompt. We're to convert it to degrees Fahrenheit.

If the current through a conductor decreases exponentially with time according to the equation \(I(t)=I_{0}\left(\frac{5}{4}\right)^{-t},\) where \(I_{0}=64\) mA is the initial current, how many seconds after \(t=0\) will the current be approximately \(26\) mA?

(A) One
(B) Two
(C) Three
(D) Four
(E) Five

The magnitude of the gravitational force acting on an object of mass \(m\) located a distance \(h\) above Earth's surface is

\[F_{g}=G\frac{M_{E}\cdot m}{(R_{E} +h)^{2}},\]

where \(G=6.67 \times 10^{-11} \text{N}\cdot \text{m}^{2}/\text{kg}^{2}\) is the gravitational constant, \(M_{E}=5.98 \times 10^{24}\) kg is the Earth's mass and \(R_{E}=6.37 \times 10^6\) m is the Earth's radius. If the International Space Station has a mass of \(4.31 \times 10^{5}\) kg and the station operates \(3.5 \times 10^{5}\) m above the surface of the Earth, what is the gravitational force acting on it?